Anyone who’s thought about science knows the promise and perils of simplification. People joke about physicists who begin working on an applied problem in agriculture by saying, “Assume the cow is a perfect sphere...”

Working on an animal in a lab is a little like assuming a cow is a perfect sphere. You can get a pretty long way by simplifying the situation. But as I’ve talked about before, you often get many unexpected and delightful findings when you let an animal be an animal, in the environment and setting that its ancestors have navigated more or less successfully for millions of years.

A new paper by Kostarakos and Römer looks how neurons work in a natural setting, using a favourite critter for this blog: crickets. Although females of many crickets species can fly, they normally walk along the ground towards a calling male. There can be a lot of “stuff” in the way of that song: grass, rocks, trees, and more. And just being close to the ground is acoustically “bad” (that’s the technical term).

Kostarakos and Römer decided to look into all this by taking their recording equipment out doors.

One of the things this comes out from such experiments, although the authors don’t emphasize it, is how sensitive cricket ears to cricket sounds. It would be easy to miss this little aside, to which I’ve added some emphasis:

(A)t greater distances, the AN1 neuron still responded to the chirps even when the microphone recordings revealed no signal.

The AN1 neurons they mention appears to be critical for the cricket to recognize and find the song of another cricket. The AN1 neurons are so key that their firing patterns are probably very good indicators of the behaviour of the intact animal. A cricket has two AN1 cells: a right and a left one, thus obeying the law of bilateral symmetry.

From recording the AN1 neurons, we find out that these little guys can pick up songs from another cricket on the order of 10 meters away. Considering that the animal is only a few centimeters long, that’s a substantial distance.

One of the surprises, though, is that it seems that every cricket has some “dull spots,” where as the animal gets closer to the signal, the neural response drops a bit. (The authors call these “silent spots,” although the AN1 response probably rarely goes to zero.) Some crickets will hear the song better at 10 meters away than they will at 8 meters away, though it picks up again when the sound gets to 6 meters away. But it was very variable from case to case, and it’s not clear if that is due to the individuals, or some peculiarities of the individual recording session. Remember, this is all out in the field, with breezes, grasses, all kinds of things happening.

Although the animal can hear the song at 10 meters away, another bit of a surprise is that at that distance, it can’t tell where the sound is coming from, that is. In a lab situation, it is laughably easy for a cricket to locate a sound 30° off center. In the field, though, with a speaker placed 30° to one side or the other, but there’s no difference in spiking activity of the left and right AN1 neurons when the sound is about 5 meters away.

Again, though, there’s a lot of variation from individual to individual. And it even fluctuates over the course of several minutes. And it fluctuates with temperature. Neurons are very temperature sensitive; you can double the firing rate of AN1 by making it about 10°C warmer.

All of which suggests that crickets are performing the important job of finding a mate with a hearing system that is a little bit wonky and unreliable. There’s dull spots, you can hear a sound but not be sure of the direction, and what you hear depends on the temperature.

One thing that might be interesting would be to use a real calling male, rather than using a “canned” song played through a speaker. Might the caller somehow tweak the song to to maximize the physiological changes in the receiver?

Given this, and some of the talks I saw at the International Congress of Neuroethology at the start of the month, recording out of doors could yield lots of new findings to work with. The science of ethology always prided itself on its emphasis of animals in their natural setting; I’m looking forward to neuroethologists reclaiming a little more of that ground truth you get from taking things into the field.

30 August 2010

Today was our first day of classes. More than any time in the past, I’m not sure I’m as ready as I should be.

As an academic, we have three things we are supposed to do: Teaching, research, and service. In theory, we are supposed to be excellent at all three of those things all the time.

In reality, there’s often times where one of those three dominates your mental life. There have been points where I have been completely gung ho to be working on an administrative task. I’m serious, so stop laughing. Other times, I’ve invested a lot of thought into thinking about how I want to teach.

But right now, I cannot stop thinking about research.

To be honest, there have been fairly long stretches where I wasn’t sure about what I was going to do next, research-wise. This is not a great feeling. This year, though, things are different. I’ve already had my most productive year of my career, and I have several different projects where I know what the next steps are. I have several manuscripts I’m ready to write up and put out the door.

And when you’re on that much of a roll, you wish that you could just ignore the other two for just a little while longer. Even though you know you shouldn’t.

When you think of cleaner fish, you probably think of those dramatically coloured little fish on tropical coral reefs, dancing in and out of the jaws of moray eels and other large predators. But coral reef fish aren’t the only ones that pick up parasites.

Pacific salmon get lice. Sea lice, to be exact. And you have to think these are about as unpleasant as human lice. Obviously, since salmon are heavily exploited, biologists are going to be interested in ways to control potentially harmful parasites that could hurt the salmon.

Losos and colleagues discovered something, apparently quite by chance: sticklebacks were picking parasites off the salmon and eating them. Good for the salmon, who gets a parasite removed, and good for the stickleback, who gets a meal. The salmon don’t seem to solicit cleaning, like some coral reef fish do, but they don’t swim away from the sticklebacks, either. And as you can see from the picture, the sticklebacks used in the experiments are about the same size as the salmon.

But that’s not the cool part.

The cool part is that the stickleback were selectively picking off female sea lice. The sticklebacks are also doing something the authors called “cropping.” Because the eggs of a pregnant sea louse are not attached to the salmon, the stickleback can grab on to the eggs alone and pull them off without removing the louse. Even if the louse isn’t killed, “cropping” probably exerts a pretty strong damping effect on the overall population of the parasites.

This is the first time cleaning has been seen in the family that sticklebacks belong to, and the first time it’s been seen in the relatively cool waters of the Canadian Pacific.

28 August 2010

Though your chief goals are the somewhat contradictory aims to rule, and then destroy, the planet Earth, you have a strong grasp of the scientific principles of blowing up things (Explodology). Good luck and please have mercy.

As an evolutionary biologist, I’m very familiar with the idea of kin selection. When I saw a paper titled “The evolution of eusociality” in the table of contents of Nature, and read the abstract saying, “Kin selection? Don’t need it,” I thought to myself, “Ooooh, this is big.”

I’ve read blog posts about it on Plektix and Wired. I listened to first author Martin Nowak being interviewed on the Nature podcast.

Novak does a good job of explaining why kin selection is invoked to invoke the evolution of sterile castes. I’ll also buy his argument that kin selection needs special conditions to work. But I have yet to read or hear a decent summary for how natural selection can pull off this feat. Novak seems to be saying that mathematically, they are the same.

The Wired article suggests that they are resorting to revived form of group selection. Third author, E.O. Wilson, has certainly been suggesting that group selection should be revived for some time (his co-author on that piece, David Sloan Wilson, is quoted in the Wired article.)

I understand that it can be hard to convey mathematical propositions verbally. But I am currently very unsatisfied with the explanations I’ve heard so far. I may not be along in this.

I am not going to have a chance to read the full paper for a while yet. The first day of our fall semester is Monday, and our library only has a subscription to the print edition of Nature.

So here is a challenge to you, fellow science bloggers! Can anyone explain the gist of this paper and how it shows natural selection explains eusociality – and do it without resorting to equations?

26 August 2010

When thinking about the evolution of nervous systems, there is sometimes a tendency to think of a sort of manifest destiny of nervous systems. It’s part of a larger tendency to see everything in evolution as part of a “march of progress,” but somehow, I think there’s a greater tendency to think about neural evolution as a tale of ever increasing complexity than bones or livers or what have you.

Examples of simplification are nice examples of exceptions. Vestigial organs have always been seen as powerful examples indicating that structures have an evolutionary history. A new paper by Lehmann and colleagues looks at simplification of grasshopper ears.

They examined four species, which ranged from animals with full wings to hoppers that are flightless. (A wingless species, Peripodisma tymphii, is shown.)Wings matter for hearing, not directly, but because one of the major selective pressures on flying insects is the desire to not be eaten by a bat – and many bats echolocate. So if you give up on flying, you are less likely to be eaten by a bat.

Perhaps the biggest difference between the four species is in the size of the eardrum: or, to use the more precise name, the tympanum. The authors claim in the discussion that there seems to be a relationship between wing length and tympanum size, which you would predict based on the considerations above. But they don’t plot it anywhere in the results.

The sensitivity of the ears differs in the four species. Slightly. All tend to be most sensitive to sounds in the 4-5 kHz range, and can usually hear sounds at higher and lower frequencies if they’re loud enough. As might be expected, though, the wingless species shown above, P. tymphii, was the least sensitive to ultrasound – the range that bats use to echolocate.

The sensory neurons, however, do not seem to be noticeably different across the four species. This suggests that differences in sensitivity is probably caused by tweaking the physiology of the neurons, not by loss of cells (although they don’t do close counts of the neurons).

Given that neurons are often thought of as being energy hungry, it’s perhaps a little surprising that the periphery changes more then the neurons do. It will be hard to judge these kinds of evolutionary tales until we get a better handle on what the costs of developing and maintaining small neural circuits is.

25 August 2010

At the recent International Congress of Neuroethology, one of the keynote talks was by Susana Martinez-Conde about the psychology of magic. She’s written a few article on illusions, and has a book on the subject coming out soon.

It was great, but it was a little unusual for a neuroethology meeting. It was all humans, so there wasn’t much ethology. And there really wasn’t a lot in the way of neurons. I wondered, “Are there magic tricks for animals?”

Maybe there is.

If you’ve played fetch with a dog for a while, you can “psych them out” by pretending to throw the ball. They’ll tear off after it... and then stop.

The essence of human illusions, psychologically, revolves around attention and expectation. To emphasize how important attention is and how unimportant concealment is, check Penn and Teller’s version of the classic cup and ball trick.

That’s right: you can have everything out in the open, and in many cases, the illusion still works.

Similarly, people’s expectation of what should happen is so strong, they will swear something happened during a magic show that did not.

It seems to me that the “fake throw” plays upon those same elements of attention and expectation in exactly the same way. I can’t help but wonder if the dog experiences this as an illusion very much like humans experiencing an illusion at a magic show. Do they actually “perceive” or “misremember” the ball being thrown? I don’t know, and more frustratingly, I can’t think of a way to test it.

Can anyone think of any other cases where animals might get fooled and experienced by some of the same tricks as humans?
Update, 15 June 2014: Hat tip to Deb Chesley for these. I like Nakke’s reaction the best.

23 August 2010

It can be a long time ago in science, too. Consider the case of Marc Hauser.

10 August: The Boston Globebreaks the story that Marc Hauser is being investigated for scientific misconduct.

19 August: The Chronicle of Higher Educationreports on accusations, including details from one of the lab’s former members who “became convinced that the professor was reporting bogus data and how (Hauser) aggressively pushed back against those who questioned his findings(.)”

20 August: USA Todaypublishes a memo from Hauser’s Dean confirming he had been found guilty of eight cases of misconduct. Later that day, Hauser admits to making mistakes and being responsible for them.

Can Hauser recover from this?

I don’t know. I have been unable to think of one scientist whose career has been able to continue uninterrupted after being found guilty of misconduct. I have distinct memories of one of my more senior colleagues saying that if you were ever caught, it would just be best to pack it in. Reputation is just too important.

Hauser might have a better chance than usual, however. Hauser is an extremely articulate person, both verbally and in print. If he is honest and forthright, he may be able to pull off an apology that allows his career to go forward. Such things are rare, but they have happened. The email USA Today published isn’t going to do it, though; he ought to write something more detailed if he wants to continue to run a lab.

If Hauser wants to continue to run original experiments, his publication process will not be like other people. He might have publish much more of his raw data, or go to unusual lengths to have them verified by independent labs. It might fall ineo the “more trouble than it’s worth” category for all concerned.

With several books to his credit and another in the works, Hauser could also step away from the lab and become a theoretician, synthesizer, and popularizer. I get the impression that his career was already on that trajectory. This may just accelerate the trend.

19 August 2010

Argiope bruennichi of the male variety are rather like Derringer pistols. Because, you see, their sex organs tend to break during mating.

Yes. Break off.

You almost can’t help but wonder if being eaten by the female – which is the fate for a large percentage of them – isn’t almost a relief to the poor boys at that point.

When you only one shot at genetic glory, you would expect to aim at the target carefully. You might expect the males to be incredibly selective about what females they mate with. In many invertebrates, there’s an easy measure of female quality: size. Bigger bodies mean more eggs.

Shulte and colleagues tested this by experiments in the field and the lab. The males had a choice between two females that differed in size. They didn’t just measure which female was mated with, but the level of the male’s interest, from “Just looking” (male comes to female’s web) to “Sure I’ll come in to see your etchings” (male enters web) to fake yawn (male courts female) to squeaking bedsprings (copulation).

The prediction is that as the differences in the two females get bigger, so too should the differences in the males’ behaviours.

The reality was... not much difference in the males’ behaviour. The males tended to go to one female very quickly and stay with that female regardless of the size, particularly in the lab. In the field, there’s more evidence for choosiness: half the males

What’s going on here? It’s not terribly clear. Maybe the cost of searching for females is so high (predation, maybe?) that the pressure is on for males to mate with the first female they meet. Maybe the male of this species doesn’t have the sensory ability to discriminate sizes, but it would be darned unusual, because lots of arthropods can do such tasks.

The males aren’t complete oblivious to the females, though. Males select quite strongly for unmated females. Because, you see, if there had been a previous male... well, let’s just say that working around the broken sex organs of a previous suitor can really cramp your style. The likelihood of siring any little spiderlets goes way down for previously mated females. But even then, some males would reject unmated females, and it’s not clear why.

18 August 2010

Sudden change creates uncertainty. This is as true in evolution as it is in financial crises. Evolutionarily speaking, eastern fence lizards (Sceloporus undulatus) are in a moment of sudden and fast change – some of them, at least.

These lizards find themselves in a situation rather like some mice I’ve talked about before (here and here). A couple of thousand years ago, a new habitat opens up with very light coloured sand. Humans, in a fit of cleverness a few thousand years later, name it White Sands, New Mexico. The lizards see an opportunity and move in. For those that do, the darkest animals tend to have a hard time of it, because their high contrast make them easy pickings for predators. Lightly coloured animals get the advantage.

The rest of the population, though, in a more normal habitat, are being not picked on for having a darker hue. So the colour of the individual in the two habitats get more and more different over time.

What happens when you put members from these two divergent populations together in the same room? Will there be any behavioural differences, or will it just be as though one lizard thinks, “Oh, my brother, though we are long separated by the shifting sands, yet I still recognize you as a member of my kind, my tribe, my species!”

It didn’t quite work out that way. When they put together two males, a male from the White Sands habitat tended to react to a darkly coloured male from another habitat with:

“Whoa. Who’s the hottie?!”

The light coloured males gave courtship displays to those dark coloured males more than half the time. This is not usual behaviour: more typically, males who get introduced to another male will usually react aggressively, because these guys are territorial.

Although the colour of the lizards’ back is the most obvious cause to point to, the authors say it’s probably not the major difference between the populations that is driving this odd behaviour. When animals are displaying to each other, they do so in such a way as to show their undersides, not their backs.

The colouring of the lizards’ undersides also varies between the white sands and the dark soils. Lizards from the white sands tend to have bigger display patches on their undersides, and this is true for both males and females. Because the display patches of females from the white sands are larger, they tend to be fairly close in size to those of the males from the dark soil environments.

Extract from Figure 4. WS = white sands, DS = dark soil.

While this seems a plausible explanation, it is an untested hypothesis at this point. And it’s not clear right why larger patches might have had a selective advantage in a light sand environment.

But you could see how anyone could make that sort of mistake. Right? Right!?

17 August 2010

At the recent International Association for Astacologymeeting, there were some student radio reporters from KBIA lurking about, and some of them came by to chat. They talked to several people, including me. I’m the second person on deck, and I talk a bit about the crustacean nociception poster I presented at the conference.

16 August 2010

Over thirty years ago, Richard Dawkins coined the term “meme” in his classic book The Selfish Gene. A meme was analogous to a gene. A gene is a physical replicator that multiplied itself (but with variations), in such a way that permitted selection and evolution. A meme, Dawkins wrote, was an intellectual replicator that could also multiple itself, creating variants as it did so, allowing evolution.

About two years ago. Susan Blackmore complained that people weren’t taking mimetics seriously, and I argued that mimetics is nowhere near being serious science.

A new paper by Cardoso and Atwell uses the meme concept in describing birdsong. On the face of it, bird song is not a bad model to use the meme concept. Some songs are easily measured; and there are distinct varieties, that are subject to some variation as they are learned.

Cardoso and Atwell looked at the songs of dark eyed juncos (Junco hyemalis) in California, where there has only been a population for about 30 years. In that time, their songs have gotten higher in pitch, which is something that tends to happen to birds in environments with lots of human created sound. They compared those to an older, more established population further from urban centers.

They’re trying to figure out if the number of modifications the birds introduce is enough to explain the change in the songs (like mutation for a gene). If it isn’t, that suggests there is another process going on, like a selective process as birds discard some songs.

If I’m understanding the authors right*, the birds change their songs slightly, but those modifications are only enough to account for about half the difference between the two populations.

The remaining difference between the two populations, they argue, came because the high frequency songs “outcompeted” the low frequency songs. But I think* they are also arguing that no selection for high pitched songs is going on right now. They say this because they reckon that if there was selection going on right now, it would be expressed by more males learning, and singing, higher-pitched songs than lower pitched songs – which isn’t the case.

In other words, the song situation appears to have stabilized. This is slightly frustrating for me as a reader, because I was hoping to get a sense of the process of song change, but it seems most of the action happened decades ago.

What I am not seeing is how characterising songs as memes leads to distinctly different hypotheses or explanations than plain old learning and communication theory does. Cardoso and Atwell are able to couch their descriptions in terms of mimetics, but I would be more impressed if they were about to use mimetics to make a explicit prediction that differed from some theory.

I haven’t changed my mind about mimetics yet.

* I have to put in that caveat that I may be getting it wrong, because this paper assumes a lot of background knowledge. For instance, me being a novice in birdsong, it’s not clear how you would group over 1,000 sound recordings into about 100 song types, or memes. There several points like that in this paper.

13 August 2010

At Slate, Christopher Beam compiles the list of usual suspects for getting rid of tenure. It includes the notions that tenure is pretty much a guarantee for life, that professors don’t care about teaching, and that they are lazy.

Keeping a professor around indefinitely—tenure means they can't be forced to retire—simply costs a lot.

Nobody in these articles ever mentions about post-tenure review. It exists. Yes, you can get rid of tenured people who are not doing their jobs. You might argue that it’s too slow, too ineffective, which I’d be inclined to agree with, but don’t say people can’t be forced out, because that’s not true.

When the best young teachers focus their energies on writing rather than teaching, students pay the price.

This is the criticism that arguably has the most teeth. There’s no question that in most places, you cannot get tenure without research accomplishments, and those are more difficult to fulfill than teaching accomplishments.

Yet nobody mentions how many faculty are fine and thoughtful teachers as well as active researchers. Teaching and research are not necessarily a zero sum game where the only way to excel at one is always at the cost of the other.

“I honestly don’t know what a lot of academics do a lot of the time,” says (Mark C. Taylor, chair of the Columbia University department of religion).

This is an astonishing thing for a department chair to say. This is one of those statements that represents a break from the reality I encounter all the time: faculty – including tenured faculty – going out of their minds trying to stay on top of all that they are asked to do. The image of the faculty getting tenure and deciding to shut down the lab and go to the pub every day in the early afternoon is a popular rhetorical device, but is it really representative?

That's one reason the number of full-time tenured professors has dropped so much in the past few decades: Women have joined the academic work force, but some have opted to take a part-time role.

Oh, so it’s womens’ fault that universities have switched to adjuncts. It has nothing to do with administrators who are looking for a fast and easy way to cut costs. And women participating part-time couldn’t possibly have anything to do with inadequate support systems, like a university not having daycare.

And if the not-so-subtle sexism wasn’t enough, there’s ageism, too:

Academia relies on young scholars to shake things up. ... By hiring someone for life, a school gambles that his or her ideas are going to be just as relevant in 35 years.

Forget old people, we all know even middle aged people can’t generate new ideas. It’s not like any major scientific work has ever been published when the author was 50, right?

I spent most of last week in Salamanca, Spain, attending the Ninth International Congress of Neuroethology. Here’s a photo set of my favourite pictures that I took around Salamanca. Salamanca has been designated a world heritage site, and it’s easy to see why. As you walk around, you constantly are confronted with views like this:

This is the sort of place where the “new” cathedral was finished in the 1600s or something. It drove home to me the truth of an old joke:

In Europe, 100 miles is a long way. In America, 100 years is a long time.

On Thursday, it occurred to me that the experience of attending a scientific conference is much like walking around in Salamanca, through the cathedrals, the university, and Plaza Mayor.

That picture above, of the facade of one of the buildings of the University of Salamanca, has a very famous feature. Can you spot it? Click here for the answer!

The New York Times features a debate section on whether anglers should catch and release fish they hook. Unsurprisingly, the vexing question of fish pain comes up again, and it’s interesting to compare the two neurobiologists who write short features (my emphasis in both quotes).

Lynn Sneddon, who was at the forefront of pioneering studies of nociception in fish (e.g., Sneddon et al. 2003), writes:

Pain perception has been demonstrated in a variety of fish, including trout, salmon, zebrafish, carp and goldfish. So it is possible that the tissue damage caused by hooking does indeed give rise to the sensation of pain and possible suffering.

It’s interesting that she says “pain perception” (which I think is problematic, because it veers into animal consciousness) rather than “nociception” (which has rock solid evidence behind it). Whether she is doing this because she is writing for a general audience who might not know what nociception means, or whether she is sold on the notion of fish pain, is not at all clear.

Some critics of angling have argued that being caught with a hook is painful to fish and that catch-and-release fishing should be banned, accordingly. The evidence presented in support of this view is not, in my view, rigorous or convincing. My research into the neurology of pain has shown that fish brains don’t have the required systems for conscious pain experience.

Right, then. What are the required systems for pain experience? And if you name specific regions of mammalian brains, I shall be cross, because that is pure chauvinism that doesn’t take into account the possibility that there can be alternative solutions to the same problem.

In my estimation, Sneddon and Rose are both being a little cavalier. Now, I freely admit that their statements are so short that it’s possible that they have more subtle views than presented here. But that brevity is a problem. Readers are left with a short “he says she says” that is likely to be confusing and make them throw up their hands and say, “Damn scientists! They can’t agree on anything!”

This isn’t the first time an article has been retracted following scrutiny from the blogosphere. In 2008, Pharyngula brought a bizarre paper in Proteomics to light. It was retracted, because it was partly plagiarized (or, as the retraction diplomatically put it, “a substantial overlap of the content of this article with previously published articles in other journals”).

This case is a more powerful indication of the influence that blogging is gaining. Plagiarism is one of the big three “No no”s in research writing, so that gives an editor a clear reason to pull a paper. This one deosn’t give the editor as simple a reason to pull the paper.

It’s not just the power of blogging on display here, but an illustration of the changing nature of publication. As more and more journals make articles available at “corrected proof” stage, there are more opportunities for bloggers to cotton to problems and prevent the worst articles from entering into the permanent record.

I was lucky enough to do a post-doc with David Macmillan. David is a wonderful person, and a terrific scientist. He was very active, and the sort of person you could see wondering, “What will I do when I retire?”

About two years ago, David got an unexpected answer: Learn to live blind.

David lost his sight in one day from an autoimmunity problem.

But thanks to the technology available now, he has barely slowed down. He continued to serve as department head and a editor of the journal Marine and Freshwater Behavior and Physiology. He jokes with fellow neuroethologists, “I reckon I have the visual system of a primitive mollusc.” He recently made the trip from Australia to Spain for the International Congress of Neuroethology, and gave a poster (David’s the one in dark glasses on the left).

Of course, being blind gives you a different perspective. David said that since he lost his sight, he realized that there are two kinds of presenters:

Those who tell a story, and use slides as a supplement to their story.

Those who make their slides, show them, and comment on them.

Even without being able to see the slides that are pervasive in scientific talks, David is able to enjoy the former. But he gets frustrated and bored with the latter.

Or, to borrow from Educating Rita, can you do it on the radio? Do you have a verbal narrative that carries you through without slides?

Again and again and again, like a drumbeat: Tell people a story. They’ll love you for it.

Day four of the conference had more excellent talks, another chance to visit posters and plug my own, but clearly the big event was the conference banquet, held at the Palacio de Figueroa. Some people complained about the price, but the food was quite nice, and the atmosphere was tough to beat.

What you can’t hear in the picture is the live jazz band. It was a bit odd to hear American jazz in such a opulent old world setting, though.

The conference organizer, Alberto Ferrus, spoke briefly...

In particular, he mentioned a group of people who were among the first people we met when we landed in Spain, dressed very distinctively (picture from conference Day -1):

Green was the conference colour, as I mentioned before. Green tote bags, green lanyard, green name tags, green fan... and the ever present, ever helpful green shirts. I never quite figured out if the Green Shirts (as they were universally known) were students, volunteers, or what have you. But they were indispensable. Thanks so much to all for helping us disoriented visitors.

The Green Shirt Team got a big round of well earned applause, and had a toast to each other:

As for day five of the conference, alas, I have nothing to report on that last day, scientifically speaking. I miscalculated the length of time it would take to get from Salamanca to Madrid, and had to leave looooong before seeing any of the Saturday talks. If anyone was there, tell me the highlights I missed!

But leaving that particular morning did give me a chance to see a bunch of other sleepy scientists, who hadn’t yet had their coffee, trying to make an escape when the sprinklers came on unexpectedly. Very funny.

On the plane, I was lucky enough to look out the window just as we were transitioning from land to sea, making this the last of Europe I’ll see in a long time. Maybe ever.

09 August 2010

There comes a moment in every biology blogger’s life when he or she must write about poop.

Well, damnit... I didn’t expect to be taken quite so literally.

Based on my post and a couple of others, Jason Goldman decides to start a carnival devoted to bodily excretions of all sorts. He floats the idea on Twitter, and is soon surrounded by what I had previously thought were reasonable people egging him on.

Suzanne Cory is an esteemed Australian scientist, and in an extensive interview in The Age, she described how all it took was a couple of great encounters with teachers to change her life.

But it was a brilliant biology teacher with a passion for the space race who first sparked Cory’s interest in science in year 9. “She came in the day Sputnik was launched and she was just transfigured with excitement.” ...

(A)nother passionate teacher changed the course of her life. An expert in the genetics of grasshoppers, his lectures were too dry for Cory's taste.

“Then one day he came in and he was a totally different person,” she says. “He was electrified by this paper he’d just read showing that the DNA in every chromosome was a single giant molecule. I think he literally imprinted on me that day a love of genes and DNA.”

Note how neither of those transformational talks are about the usual things we talk about in science classes. The tried. The true. The proven. The stuff done decades, if not centuries, before we were born, never mind our students.

Instead, it’s talking about the things that genuinely excites us, the instructors, that can excite our students.

08 August 2010

As to my biggest frustration—it is people’s lack of desire to test anything. This occurs in the governments, companies, and even at individual levels. For example, when I visit companies I often try to push companies to test different compensation arrangements. Almost always I am met with avoidant responses—people would say, ”Everyone is so miserable about their bonuses, etc. We can’t talk about it –maybe next year.” So eventually, no one does any testing and this way it is very hard to make any progress.

Now I’m not trying to suggest that companies are stupid. For one, lawyers make it very difficult to test things. But, it seems that in general humans have an aversion to testing. Using experiments to answer questions just doesn’t seem satisfying for most people.

06 August 2010

There comes a moment in every biology blogger’s life when he or she must write about poop.

This is one of those moments.

When a paper’s title includes phrase, “fecal particle size,” sometimes, one just thinks, “Okay, I really should read that, if for no other reason than it was clearly a lot of unpleasant work for someone.”

The intellectual issue here relates to the difference digestive strategies of mammals and reptiles. Mammals chew; reptiles generally don’t. This has a lot of consequences. It means mammals can spend a lot less time digesting food. This, in turn, helps to make the high-energy endothermic lifestyle that mammals enjoy possible. And it means that mammals should have feces that are more... fine-grained, if you will. You’re not likely to find something like this in the droppings of a mammal:

The authors recovered this particular leaf from the feces of a common iguana.

But this is science, damnit, not a schoolkid’s joke! We need quantifiable data on the particles in poop! We need to test those turds!

So, Julia Fritz and her four co-authors collected a lot of samples from fourteen reptiles species held in European zoos. Then, they started sieving all those feces. They had a few predictions about what they’d find. The major one, that the reptiles’ feces would have large particles, was confirmed. They had also predicted that large bodied animals would also tend to have coarser feces, probably due to bite size.

They also predicted that animals fed prepared food would tend to have larger particles, reasoning that those feeding on plants in the ground would be able to manipulate the plant in ways that allowed the reptiles a chance to regulate the size of the bites they took. They tested two tortoise species, and found the effect in one, but not the other. So the story is a little equivocal here.

Now, you may think that you’ve heard about reptiles using stones in their stomach to break down their food. Fritz and company find no evidence of that at all. It’s a little surprising, as I would have thought this would be something that would have been settled long ago.

As an outsider to the digestive physiology field, it’s a bit difficult for me to figure out what the next logical set of questions to ask is. The authors, however, say that one thing they would like to do is get a lot of excrement from free-ranging reptiles. They modestly note that this is “a major logistical challenge.”

Neuroethology continues to go well. My poster was up today, and will be up tomorrow for any blog readers who haven't introduced themselves yet!

The day concluded with the business meeting, which included two fine proposals for the Congress after the next one (tenth International Congress of Neuroethology will be at the University of Maryland in 2012).

Björn Brembs is managing to liveblog from the even (barely), with these posts on neuroeonomics and habituation. That Björn is having wifi problems is perhaps his just punishment for bring a poster to neuroethology with no neurons anywhere in sight.

These little sharpshooters are famous for being able to spit water at an insect, not on the surface of the water, but a good ways above it. And these insects are often camouflaged to boot. Then, they have to catch the insect when it hits the water before other fish get it, or it gets swept away by any water currents.

In other words, archerfish have to calculate, perform precision maneuvers, and anticipate the outcomes of their actions.

This paper, though, looks mainly at the visual problem. Anyone has probably noticed that light behaves differently when it moves through water than when it moves through air. The famous example that every kid has probably asked his parents about is why a spoon in a glass of water looks like the two halves are broken apart.

The authors here looked at the properties of the photoreceptors in the archerfish eyes. Something to remember is that the top of the retina looks down, which for the archerfish means into the water, and the bottom part of the retina looks up, which for the archerfish means looking up and out of the water. Now, it gets a bit sticky because fish have more complicated eyes that we primates do. We have rods and three kinds of cones. The archerfish has rods, single cones and double cones.

First, they found that the three general areas of the eye they looked at, the light-sensing cells of the ventral part of the retina had rather different light absorbing properties than the rest. This correlates with the fish’s visual task: the bottom part of the eye looks up, out of water.

As light goes through the water, the colours change. At the top of the water, the light tends to have shorter wavelengths than the light being reflected from the bottom of the water. The sensitivity of the photoreceptors in those regions matched quite well with the different kinds of light these animals would be seeing.

The highest density of cones is also right in the “sweet spot” where the fish will be looking at its target. The authors don’t use the term “fovea,” but it seems to me that is exactly what it is. And the resolution the archerfish is probably capable of is estimated to be about 8 minutes of arc; by comparison, arthropods eyes tend to be only able to resolve several degrees of arc, and I think humans in fractions of a second of arc.

They interpret these differences across the retina as adaptations to living at the interface, which is perfectly reasonable. The authors suggest that it something that other fish living near the surface have, although one might expect it to be particularly enhanced in the archerfish.

Next steps for this group is to start doing a bucket of behavioural tests to see how well the fish is able to discriminate different colours, shades, and so on. Since the fish has a nice behaviour of spitting at things they see, it should be possible to train them to spit at objects they can see, then tweak the visual stimuli until they can’t do the task any more.

Reference

Temple, S., Hart, N., Marshall, N., & Collin, S. (2010). A spitting image: specializations in archerfish eyes for vision at the interface between air and water Proceedings of the Royal Society B: Biological Sciences, 277 (1694), 2607-2615 DOI: 10.1098/rspb.2010.0345

Yeah, let’s criticize that she didn’t get past the first impression of science blogs. We should expect Heffernan to look before leaping – she writes for the Times, after all, which still has a certain reputation as a paper of record and quality. But let’s not pretend that her impression ain’t shared by anyone else.

For instance, she took heat for recommending a climate denialist blog. But that’s not the first time that blog got recommended by people who ought to know better. That tells me there’s something we can learn there.

When we read Heffernan’s piece, we don’t like it. She was bound to get a lot of, “You don’t know what you’re talking about” (which, like I said, she earned). But she’s not getting as much, “Would you like to learn?”

Now, because she is a public figure, and counts people like David Dobbs among her colleagues, we might be able to convince her we ain’t so bad. Win for us if we do.

But a lot of us are probably just going to give her up as a lost cause. “She didn’t like the science blogosphere? Tough noogies. Good riddance.”

Bora nailed it when he wrote about the power that the Science Blogs website in particular had, but it’s true for the rest of us. There’s probably a lot of other people who have reactions like Virginia, but don’t blab about them in such a public forum. So they go away all quiet-like, and nobody makes the effort to reach out and invite them back.

We can do better than, “Don’t let the door hit your ass on the way out.”